The present invention relates to a method and apparatus for sealing the lower portion of an exterior wall system which also acts as a chemical (termiticide and/or pesticide) application appliance and to a method for applying chemicals to a structure. In particular, the present invention is intended to be used both to mechanically seal the exposed area created at the lower portion of the exterior walls of a structure, such as a residence, while simultaneously providing a means for facilitating the injection of chemicals (termiticides and/or pesticides) between the inner and outer portions of the exterior wall system, thereby providing a perimeter pest control system which extends around the periphery of the structure.
In the past there have been efforts to provide chemical (termiticide and/or pesticide) treatment to protect structures at the time that they are constructed. While it has been common practice in the construction of new buildings to pre-treat the fill or soil area which is to underlie the foundation with a termiticide, the initial termite barrier does not last indefinitely, so there is a need to supplement this barrier during the life of the building by providing an efficient and inexpensive means at the points where termites or other insects can gain access to wooden structural members. While termites do not bore holes through concrete, they can gain entry into the areas where wood is used in the construction of the building by forming earthen tunnels from ground level over the surfaces of concrete foundations, slabs, and walls. A common problem in buildings clad with exterior surfacing materials such as lap siding, which includes, but is not limited to wood, cement-fiber, composites, vinyl, and aluminum, is that even if the siding itself is made of a material which resists rotting, cracking, damage from rain or hail, or insect penetration, the exterior board siding is installed in lapped layers over the exterior portion of the internal wall structure, whereby an exposed area is formed behind the lowest board, e.g., between the rear (inner) surface of the lowest board and the outer surface of the foundation wall, which would permit insects to climb from the ground up and gain access to the structure via the exposed area. For example, even such popular construction materials as cement board siding, e.g., those sold by James Hardie Building Products, called “Hardie Board”, while themselves impervious to insect penetration, permit insects to gain access in the exposed area formed behind the lowest board.
In particular, termites are able to build tunnels in the tiny spaces between the walls and the surfacing material, and their tunneling activity will not be detected because it is behind the cement board exterior surfacing material. Thus, while the exterior surfacing material will prevent termites or other insects from gaining access through them, the lack of a seal between the exterior portion of the internal structural wall and the interior portion of the exterior surfacing material provides a path through which termites or other insects can enter the structure from behind the exterior surfacing material.
This situation can be made worse if landscaping activities decrease the vertical space between the ground and the upper portion of the foundation wall following construction which make it even easier for termites and other insects to gain access by climbing up the edges of a foundation slab and between the structural walls and the exterior siding material without being detected until after severe damage has been done to wooden structural members of the building.
Prior methods for preventing termites and other insects from entering between the structural walls and the exterior siding material involve saturating the soil adjacent to the perimeter of the structure with chemicals (termiticides and/or pesticides) at the point of termite entry. This is accomplished by trenching or rodding. In the first of these methods, a trench is dug around the perimeter and filled with termiticide, e.g., at the rate of about four gallons of chemical (termiticide and/or pesticide) per linear foot of trench. In the other method, chemical (termiticide and/or pesticide) is injected through a hollow rod jammed into the soil and against the foundation about every six inches or so. Usually the soil adjacent the foundation is relatively dry. Since dry soil does not absorb liquids easily, it is not uncommon for chemicals (termiticides and/or pesticides) applied in this manner to drain away very quickly, thereby making it ineffective at the point of termite or insect entry, and, instead, creating an environmental detriment to the surrounding soil. Further, these methods are quite labor intensive, so they are costly to use. Thus, there has been an ongoing need for an efficient, labor-saving chemical (termiticide and/or pesticide) delivery system for providing an effective perimeter pest control system to create a barrier between the exterior cladding of a building and its foundation and exterior structural walls, whereby the area between them can be sealed from insect intrusion while also providing a means for easily treating the structure on a periodic basis.
While a number of fluid distribution systems for chemicals (termiticides and/or pesticides) comprised of conduit capable of emitting chemicals through apertures or valves have been developed for incorporation in or under a building foundation, these prior systems are typically quite elaborate in construction, requiring extensive modification of traditional and conventional building methods, expensive pumps and reservoirs, and substantial increases in building costs. Such issues have been previously noted, for example, in U.S. Pat. No. 3,513,586 to Meyer et al. which discloses and teaches a distribution system comprising tube means disposed within a building footer constructed of conventional concrete building blocks, requiring additional support members and plate members, among other things, that but for the distribution system, would not be required as part of the footer.
U.S. Pat. No. 3,209,485 to Griffin discloses a pesticide distribution system comprised of multiple, independent, branched circuits, intended to be installed within and under a foundation at the time of construction. The system comprises many parts, and its installation requires multiple steps at different stages of construction of the building.
U.S. Pat. No. 3,602,248 to Peacock discloses a distribution system comprised of a plurality of parallel connected pipe branches, each branch thereof short enough so that fluid pressure is maintained along the entire piping, with at least two inlets into each branch. Each branch requires a closure fitting at the end opposite the inlet end. Multiple pumps are required to maintain uniform pressure in the branch lines.
There are also a number of related systems for distributing pesticide within the walls of buildings. In U.S. Pat. No. 3,676,949 of Ramsey, pipes with emitter nozzles pass through the studs of the walls with a nozzle disposed between each set of studs. In U.S. Pat. No. 3,782,026 of Bridges et al., pipes extend within the walls or, alternatively, beneath baseboard moldings on the interior walls, permitting injection of insecticide gas within the walls. In U.S. Pat. No. 4,028,841 to Lundwall an insecticide storage and pressurizing system is installed in the attic, and perforated pipes carry pest control fluid into the building walls, while U.S. Pat. No. 4,742,641 to Cretti describes a built-in reservoir which is installed within a building wall from which pesticide is distributed whenever the pump is operated (which can be done by a timing device for injecting predetermined amounts at predetermined spaced intervals).
U.S. Pat. No. 3,330,062 to Carter is another pest control system utilizing pipes installed through holes drilled through the wall studs of a building with the pipes requiring threaded caps at their distal ends. U.S. Pat. No. 4,944,110 to Sims relates to a method for applying pesticide into the concealed areas of a building, by injecting pressurized chemicals through perforated preinstalled tubing. U.S. Pat. No. 5,347,749 to Chitwood et al. discloses a system for reapplication of termiticide to the fill dirt underlying the foundation slab of a building at potential termite entry points: junction of foundation block with slab, and openings in the slab for penetration of bundles of utility connections.
While none of the foregoing patents teaches or discloses a system adapted to deliver a termiticide barrier to the exterior walls of a building underneath its surface coating or siding materials, an effort to disclose such a system was made in U.S. Pat. No. 5,819,466 to Aesch, et al., in which a peripheral termiticide delivery system using flexible apertured tubing was described. That system was designed to simply saturate the exterior foundation walls of a new structure, with the treatment going down to the soil.
U.S. Pat. No. 6,301,849 which issued to Roth describes a flashing article used to seal out moisture and to drain moisture away from a stucco coated exterior wall surface. In order to provide chemical treatment, the article uses one or more tubes, an internal conduit, and connectors, all of which prevent the article from being made as an extruded item. Further, the installation of the article is considerably more labor intensive than would be desirable, as each installation requires custom fitting the article to each wall section of the structure. In addition, the flashing overlies the lower portion of the exterior wall which prevents a good seal without caulking, which adds yet another complexity and expense to the installation. Notably, if the caulk seal between the outer surface of the flashing and the structure were to fail, the flashing would actually act like a gutter system, and funnel water under the exterior wall system, thereby creating potential damage to the exterior wall system and introducing moisture between the exterior and interior wall systems.